Tension and rivalry between France and Germany shaped the history of Western Europe in the century from 1860. Three times that hostility led to war and the invasion of France - in 1870, 1914 and 1940. The outcomes of the battles that followed reset the balance of power across the continent. Yet the German invasions tend to be viewed as separate events, in isolation, rather than as connected episodes in the confrontation between the two nations. **Douglas Fermer's fresh account of the military campaigns and the preparations for them treats them as part of a cycle of fear, suspicion, animosity and conflicting ambitions extending across several generations. In a clear, concise account of the decisive opening phase of each campaign, he describes the critical decision-making, the manoeuvres and clashes of arms in eastern France as German forces advanced westwards. **As the 100th anniversary of the start of the Great War approaches, this is a fitting moment to reconsider these momentous events and how they fit into the broad sweep of European history.